Answer:
that people must have a say in the laws that they follow
Step-by-step explanation:
Taxation without Representation was the American colonist's slogan to show their opposition to the idea of being taxed by the British Parliament of which they have no representatives. Hence, this implies that American colonists should at least have a say in the rules and regulations that govern them.
Hence, in this case, the Enlightenment idea they were demonstrating is " that people must have a say in the laws that they follow."